Tadalafil (BPH)

How it works

It inhibits phosphodiesterase type 5, preventing the breakdown of cyclic GMP and prolonging smooth muscle relaxation and vasodilatation in the corpus cavernosum and lower urinary tract; its long duration of action distinguishes it from shorter-acting agents in the class.

Prescribing in practice

• It is contraindicated with nitrates and with nicorandil because the combination can cause severe, potentially life-threatening hypotension.
• Use with caution alongside alpha-blockers and other antihypertensives, and in men with significant cardiovascular disease or recent stroke or myocardial infarction; consult the SPC.
• Prolonged or painful erection (priapism) can occur and requires urgent medical attention.

Monitoring

Confirm the patient is not taking nitrates or nicorandil and assess cardiovascular fitness before use. Review blood pressure and symptoms where alpha-blockers or other antihypertensives are co-prescribed, and reassess response and tolerability.

Counselling the patient

• Never take this medicine with nitrate heart medicines (such as GTN sprays or tablets) or with nicorandil, as your blood pressure could drop dangerously.
• Seek urgent medical help if you have an erection lasting more than four hours.
• Tell your prescriber about any heart problems, and stop and seek advice if you develop chest pain, sudden vision changes or fainting.

Evidence & guidelines

A phosphodiesterase-5 inhibitor recommended in UK guidance (NICE) for benign prostatic hyperplasia and erectile dysfunction, with the nitrate contraindication a long-standing class safety point.